Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Part IV. Renewable Resources A. Fish B. Forests C. Water D. Biodiversity 1 C. Water Chapter 15 2 Introduction • 4 distinct problems have arisen that affect the availability of water: 1. In many areas of the country the use of water exceeds the rate at which it is being replenished. 2. Many activities use water as an input, and when the water is returned to surface or groundwater, its quality is diminished. 3. Many activities use surface or groundwater as a means to dispose of waste, creating water quality problems. 4. Degradation of ecosystems weaken their ability to store water and modulate the drought/flood cycle. 3 Water Consumption • Within the resource taxonomy there are 3 categories: 1. Renewable resources, in which the stock regenerates itself 2. Resource flows, where a never-ending flow comes from a nondepletable stock 3. Exhaustible resources, fixed amount *****Water can be described as all 3***** 4 Renewable • Water, in general, meets the definition of a renewable resource, where the evaporation from the oceans and other water sources creates the precipitation that replenishes the oceans. • Smaller water bodies, however, do not generally replenish themselves. • The evaporation from a river does not provide the water source for a river (with the exception of very large systems like the Amazon) 5 Resource flow • Water in riverine systems can be viewed as a resource flow. • The water that arrives at any particular point along the river is independent of the amount of water that is taken out at that point. • More important, a decision to remove water today will not affect the amount of water that is taken out tomorrow 6 Exhaustible • However, can view river water as exhaustible in the sense that an upstream user’s decision to remove water reduces the amount of water available to downstream users. • Some water resources can be viewed as exhaustible because the rate of growth of the stock is small in relation to the use of the water. • "Fossil water," which is water that has accumulated slowly in underground aquifers over millions of years is an example of an exhaustible resource. 7 Water availability • If the flow of a river is much larger than the withdrawals of water to meet consumptive and productive needs then there will be no resource allocation problem, even if the water is available at zero cost. • However, if the flow of water is not capable of meeting all needs at any point in time then a shortage will develop. • At a price of zero, quantity demanded of water is greater than amount available and as price rises, the least valuable needs will be left unsatisfied. • If price is continually raised, eventually quantity demanded will equal the amount of water available. 8 Scarcity and the price of water • Figure 15.1 illustrates how essential scarcity is in determining price. • In this figure g0 represents the daily volume of water that may be removed from the river. • The cost of extraction is zero. • Demand is represented by D1. • Under these circumstances, all the demand that exists at zero price will be satisfied. • However, if Demand increases to D2, all the demand at zero price cannot be satisfied. • As demand increases, the opportunity cost/user cost of consuming the fixed flow of water increases, which is reflected in the increased price (remember, assumed MEC = 0) 9 10 Property rights • Property rights must be well defined in order for a market and a price to exist. • Price will also reflect the MC of producing water. • The cost of producing water takes the form of purification, transportation, etc. • If property rights are not well defined or other conditions result in market failure, then the price will be too low and this will lead to shortage as illustrated in Figure 15.2. • Here, the price at which quantity demanded equals fixed quantity supplied is p0, but a price of p1 would lead to a shortage equal to g1-g0. 11 12 Property rights • Property rights to water are a big issues in the Western US where most rights are defined on a state-by-state basis. • Appropriation-based water rights make water available for use by anyone who can apply it to a beneficial purpose. • Priority goes to the user who establishes his or her appropriation-based rights first. • Initially these rights were nontransferable but increasing demand for water has led western states to make them transferable. • This has created a market for water and the potential to use market mechanisms to protect ecological uses of water. 13 Water as resource flows • In eastern and Great Lakes states, water resources can be viewed primarily as resource flows, where most cities and agricultural areas depend on surface water or groundwater that is generally replenished by normal rainfall. • One mechanism that often leads to urban water problems is the process by which water is priced and distributed to customers. • This is usually done by either a regulated water utility or a municipal water company. • In both cases there are political or regulatory forces that push the price of water below its opportunity cost. 14 Monopoly water pricing • When water is provided by a regulated monopoly, the scarcity value of water is not incorporated into the price, only costs of the other inputs used in purifying and distributing water. • If the price of water is below the opportunity cost, a shortage will develop and other means will have to be used to allocated the water. • There is no guarantee that these alternative methods will result in an efficient allocation of the water. 15 Public pricing • Alternatively, if a city elects to provide distribution of water as a city service, political pressures may keep rates low (e.g., agricultural special interests), again allowing no mechanism for reflecting the value of alternative uses. • When consumers of water in an apartment building pay a rate based upon use by the entire building (average price) rather than an individual rate (marginal price) there is no strong incentive to conserve use (condominiums – whole building 16 metered, not individual units) Public pricing • Even if water is priced according to marginal willingness to pay, there may still be market failure if the pricing structure does not reflect the ecological opportunity cost of water (flows of water necessary for aquatic life). • 2 basic ways to reflect the ecological opportunity cost of water include: 1. Government tax on water use 2. Purchase of water rights by NGOs where the water is left in the stream. 17 Water as an Exhaustible Resource • Water resources in western states are better described as exhaustible resources (rate of use > recharge) • The economic analysis of water as an exhaustible resource is very similar to the analysis of water as a resource flow, only there is an additional opportunity cost. 18 2 opportunity costs 1. The first opportunity cost is the cost of not having water for another current use, the contemporaneous opportunity cost. 2. The second is the opportunity cost of not having the water available for future use, which results from current use depleting the stock available, which is called the intertemporal opportunity cost. • An efficient allocation of water would require that the price reflect both contemporaneous and intertemporal opportunity cost. 19 Degrading Uses of Water There are 3 types of uses that degrade water quality. 1. Removal of water from surface water bodies or groundwater aquifers generates ecological damage. Heavy water withdrawal in the coastal area of southern Florida has lead to saltwater intrusion into the aquifer. 2. When a direct consumer of water uses it and returns it to hydrological cycle with wastes and contaminants. E.g., residential use of water which adds human wastes: even when treated, the water has a higher level of nutrients which can cause ecological damage. 3. Activities that generate wastes that are directly deposited into or make their way through natural mechanism such as run-off from rainfall. E.g., rainfall run-off that carries pesticides from agricultural fields. 20 21 US Policy Toward Water Pollution • U.S. policy toward water pollution has historically focused on large point sources of pollution. • Point sources of pollution are those where the pollution enters the water body at a specific point, such as the end of an effluent discharge pipe. • One of the major thrusts of attempts to reduce water pollution was a program to reduce the impact of the discharge of municipal sewage. 22 US Policy Toward Water Pollution • Amendments to the Clean Water Act required all municipalities to develop and upgrade their sewage treatment facilities. • Programs were designed so that the federal government would pay 75% of the costs of the facility, and the local government would be responsible for the remainder of the construction costs and for operating costs. • The primary reason for the federal government involvement was that the social benefits to the nation of treating a community’s wastewater was greater than the social benefits to the community. 23 Command and control • The subsidized improvements in municipal sewage treatment plants were required by the Water Pollution Control Act of 1972, the Clean Water Act of 1977, and 1977 and 1978 amendments to the Clean Water Act (CWA). • These acts, based on command and control techniques, also focused on other large point sources of pollution, such as paper plants, food processing facilities, and other industries. 24 Command and control • The National Pollution Discharge Elimination System (NPDES) made all discharges illegal unless authorized by NPDES. • Polluters were required to use best practical technology (BPT) for conventional pollutants and best available technology (BAT) for toxic pollutants. • BPT allows for the consideration of cost of the technology, BAT does not. 25 Economic incentives? • Economic incentives have not been employed to deal with water quality problems. • While it would be feasible to develop a system of marketable pollution permits, it would require more interstate cooperation, since all the major river systems span several states. • The use of command and control policies created the same types of problems discussed in earlier 26 chapters. C & C problems • The CWA and associated amendments have not been completely successful in meeting the legislative goals of restoring and maintaining the chemical, physical, and biological integrity of the nations’ water. • There has been some mixed success in reduction of organic wastes from point source polluters. • However, where nonpoint pollution is a major problem, the water quality remains poor. 27 Nonpoint source pollution • Associated with agricultural, urban, and suburban run-off. • Recently new regulations have been developed requiring farmers to institute “best farming practices” to control nutrient run-off and soil erosion. • Agriculture remains one of the largest contaminators of water resources in the parts of the US and in developing countries. 28 Nonpoint source pollution • Even though some progress has been made in controlling organic pollutants, the problem of toxic pollutants has not been similarly reduced. • Many areas with healthy fishing populations also have prohibitions against consumption of the fish due to the high levels of contamination by toxins such as PCBs, mirex, dioxin, and heavy metals. 29 International Water Issues • The water problems in other countries (particularly developing countries) may be more severe than in the United States. • The primary water problem in developing countries is the contamination of water by untreated human waste. • This is true not just in villages, but also in very large urban areas such as Rio de Janeiro, where large slums intensify the waste problem. • This is not just a third world problem. In the Po River Valley in northern Italy, many cities (including Milan) dump untreated wastes into the river. • The Mediterranean Sea suffers from extreme water pollution problems which are expected to increase as North Africa becomes more industrialized. 30 Transfrontier Externalities • The water consumption and waste disposal activities of one country affect water availability and water quality in neighboring countries. • This is particularly true in the Middle East, where geographically small countries overlie common aquifers and where rivers such as the Jordan River and the TigrisEuphrates River drain several countries. • These transfrontier externalities cannot be internalized without international agreement. • The US has longstanding agreements with Canada concerning water use and water quality in boundary areas, and a special commission to deal with Great Lakes issues. • Agreements with Mexico are being developed. 31 Summary • Although the earth’s surface is ¾ covered by water, uncontaminated water is a scarce resource. • Many market failures, including externalities, nontransferable property rights, and poorly conceived regulatory practices contribute to the scarcity. • From a US and international perspective, one critically important policy change would be to price water so that it included its full opportunity cost. • This would include the opportunity cost of both current and future uses of water, as well as the costs associated with reductions in the quality of water resources. 32